We were here because I thought it might help soften her up before I apologized for what I’d done to her friend Pete the month before. But instead of unwinding or letting me tell her about my latest office project, she’d switched into hypercritical mode as soon as we got to our booth. Apology shelved. Perhaps she’d just had a bad day at the office, but begging forgiveness for sins of necessity committed in the line of duty was clearly off the menu for the time being. Ten years together, seven of them married, have taught me to recognize the signs: right now if I reminded her that the sun rose in the east she’d start by stonewalling then escalate to a land war in Asia.

“Bob.” When she said my name like that, it gave me flashbacks to Miss Pearson in Primary Two (not my favorite teacher): “Vampires can’t exist. There’d be detailed records in the archives; they couldn’t possibly evade detection by the state for any significant period. Besides which”—she aimed an alarmingly sharp wooden chopstick at my nose—“there’d be corpses everywhere. Human blood is a poor nutrient source; it’s about 60 percent plasma by volume and only provides about 900 calories per liter, so your hypothetical blood-sucking fiend is going to have to drink about two and a half liters per a day. Those calories don’t come in the form of useful stuff like glucose and fat: it’s mostly protein from circulating red blood cells. Dracula would have to exsanguinate a victim every day just to stay alive, and would suffer from chronic ketoacidosis. The total number of intentional homicides for the whole country is around 700 a year; a single vampire would cause a 50 percent spike in the murder rate. Or they’d have to take transfusion-sized donations about two thousand times a year.” She capped the boss-level takedown with a tight-lipped, triumphant smile, the better to conceal her incisors: “If you think you, or I, or anyone in the office could mind-control hundreds of people well enough to prevent at least one of them going to their GP to complain about the lethargy and anemia . . .”

I gave in to the inevitable. “You’ve researched this already, haven’t you?”

“It came up in a brainstorming exercise about six years ago. We were investigating using ecosystem analysis to evaluate the probability of emergent new threat modalities. We also brainstormed golems, werewolves, and sasquatch.” She took a spoonful of miso soup. “If they existed we’d know about them, Bob.”

“But”—I paused to swallow my squid and pluck another one from the color-coded plate in front of me—“your model assumes they’re obligate hemophages, doesn’t it? And that they’re endothermic, or at least have an energy budget not entirely unlike every other vertebrate known to science. What if that’s not the whole story? What if they eat—”